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PERIODIC MAINTENANCE AND MINOR REPAIR
6-22
6
EAU00731
Inspecting the brake fluid
levelInsufficient brake fluid may let air enter
the brake system, possibly causing the
brakes to become ineffective.
Before riding, check that the brake fluid
is above the minimum level and replen-
ish when necessary.
Observe these precautions:
l
When checking the fluid level,
make sure the top of the master
cylinder is level by turning the han-
dlebars.
l
Use only the designated quality
brake fluid. Otherwise, the rubber
seals may deteriorate, causing
leakage and poor brake perfor-
mance.
l
Refill with the same type of brake
fluid. Mixing fluids may result in a
harmful chemical reaction and
lead to poor brake performance.
l
Be careful that water does not en-
ter the master cylinder when refill-
ing. Water will significantly lower
the boiling point of the fluid and
may result in vapor lock.
l
Brake fluid may deteriorate paint-
ed surfaces or plastic parts. Al-
ways clean up spilled fluid
immediately.
l
Have a Yamaha dealer check the
cause if the brake fluid level goes
down.
1. Minimum level markFront
1. Minimum level markRecommended brake fluid: DOT 4Rear
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-24
6
EC000096
CAUTION:@ Too little chain slack will overload
the engine and other vital parts.
Keep the slack within the specified
limits. @3. After adjusting, tighten the axle nut
and caliper bracket bolt to the
specified torque.
EAU03006
Drive chain lubricationThe chain consists of many parts which
work with each other. If the chain is not
maintained properly, it will wear out
quickly. Therefore, the chain must be
serviced regularly. This service is es-
pecially necessary when riding in dusty
areas. This motorcycle is equipped
with a sealed type chain. Steam clean-
ing, high-pressure washers, and sol-
vents can damage the drive chain, so
do not use these for cleaning it. Use
only kerosene to clean the drive chain.
Wipe it dry, and thoroughly lubricate it
with SAE 30 ~ 50W motor oil. Do not
use any other lubricants on the drive
chain. They may contain solvents that
could damage the sealed chain.
EC000097
CAUTION:@ Be sure to oil the chain after wash-
ing the motorcycle or riding in the
rain. @
EAU02962
Cable inspection and
lubrication
EW000112
WARNING
@ Damage to the outer housing of ca-
bles may lead to internal rusting and
interfere with the cable movement.
Replace damaged cables as soon as
possible to prevent unsafe condi-
tions. @Lubricate the cables and cable ends. If
a cable does not operate smoothly, ask
a Yamaha dealer to replace it.
1. Caliper bracket bolt
Tightening torque:
Axle nut:
110 Nm (11.0 m·kg)
Caliper bracket bolt:
35 Nm (3.5 m·kg)
Recommended lubricant:
Engine oil
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-28
6
EAU01144
Wheel bearingsIf there is play in the front or rear wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer in-
spect the wheel bearings.
EAU00800
BatteryThis motorcycle is equipped with a
sealed-type battery. Therefore it is not
necessary to check the electrolyte or fill
the battery with distilled water.l
If the battery seems to have dis-
charged, consult a Yamaha deal-
er.
l
If the motorcycle is equipped with
optional electrical accessories, the
battery tends to discharge more
quickly, so be sure to recharge it
periodically.
EC000101
CAUTION:@ Never try to remove the sealing caps
of the battery cells. The battery will
be damaged. @
EW000116
WARNING
@ Battery electrolyte is poisonous and
dangerous, causing severe burns,
etc. It contains sulfuric acid. Avoid
contact with skin, eyes or clothing.
ANTIDOTE:l
EXTERNAL: Flush with water.
l
INTERNAL: Drink large quanti-
ties of water or milk. Follow with
milk of magnesia, beaten egg,
or vegetable oil. Call a physi-
cian immediately.
l
EYES: Flush with water for
15 minutes and get prompt
medical attention.
Batteries produce explosive gases.
Keep sparks, flame, cigarettes etc.,
away. Ventilate when charging or
using in an enclosed space. Always
shield your eyes when working near
batteries.
KEEP OUT OF REACH OF CHIL-
DREN.
@
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8-1
8
EAU01038
8-SPECIFICATIONSSpecifications
Model TDM850
Dimensions
Overall length 2,165 mm
(for GB, NL, B, F, E, P, I, GR, D,
DK)
2,200 mm (for N, S, SF)
Overall width 790 mm
Overall height 1,285 mm
Seat height 805 mm
Wheelbase 1,475 mm
Ground clearance 165 mm
Minimum turning radius 2,900 mm
Basic weight (with oil and full
fuel tank)
232 kg
Engine
Engine type Liquid cooled 4-stroke, DOHC
Cylinder arrangement Forward inclined parallel
2-cylinder
Displacement 849 cm
3
Bore ´ Stroke 89.5 ´ 67.5 mm
Compression ratio 10.5:1
Starting system Electric starter
Lubrication system Dry sumpEngine oil
Ty p e
Recommended engine oil
classification API Service SE, SF, SG type or
higher
Quantity
Periodic oil change 3.5 L
With oil filter replacement 3.6 L
Total amount 4.2 L
Cooling system capacity
(total amount)
1.7 L
-20˚ -10˚ 0˚
10˚20˚ 30˚
40˚50˚C
SAE 10W/30
SAE 15W/40SAE 20W/40SAE 20W/50
SAE 10W/40
CAUTION:Be sure to use motor oils that do not contain anti-friction
modifiers. Passenger car motor oils (often labeled
“Energy Conserving”) contain anti-friction additives which
will cause clutch and/or starter clutch slippage, resulting in
reduced component life and poor engine performance.
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SPECIFICATIONS
8-3
8
Maximum load* 203 kg
Air pressure (cold tire)
Up to 90 kg load*
Front 225 kPa (2.25 kg/cm
2, 2.25 bar)
Rear 275 kPa (2.75 kg/cm2, 2.75 bar)
90 kg load ~ maximum
load*
Front 225 kPa (2.25 kg/cm2, 2.25 bar)
Rear 275 kPa (2.75 kg/cm2, 2.75 bar)
High speed riding
Front 225 kPa (2.25 kg/cm2, 2.25 bar)
Rear 275 kPa (2.75 kg/cm2, 2.75 bar)
* Load is total weight of cargo, rider, passenger and accessories.
Wheels
Front
Ty p e C a s t
Size 18 ´ MT3.00
Rear
Ty p e C a s t
Size 17 ´ MT4.00
Brakes
Front
Type Dual disc brake
Operation Right hand operation
Fluid DOT 4Rear
Type Single disc brake
Operation Right foot operation
Fluid DOT 4
Suspension
Front
Ty p e Te l e s c o p i c f o r k
Rear
Type Swingarm
Shock absorber
Front Coil spring / oil damper
Rear Coil spring / gas-oil damper
Wheel travel
Front 149 mm
Rear 144 mm
Electrical system
Ignition system T.C.I. (digital)
Charging system
Type A.C. magneto
Standard output 14 V, 23.5 A @ 5,000 r/min
Battery
Type GT12B-4
Voltage, capacity 12 V, 10 AH
Headlight typeQuartz bulb (halogen)
E_4tx_Spec.fm Page 3 Saturday, October 16, 1999 9:38 AM